git: bde1cafb7c2b - stable/13 - iflib: Allow drivers to determine which queue to TX on

From: Eric Joyner <erj_at_FreeBSD.org>
Date: Tue, 08 Mar 2022 00:21:38 UTC
The branch stable/13 has been updated by erj:

URL: https://cgit.FreeBSD.org/src/commit/?id=bde1cafb7c2b65c111e4da33f578844bc25404cd

commit bde1cafb7c2b65c111e4da33f578844bc25404cd
Author:     Eric Joyner <erj@FreeBSD.org>
AuthorDate: 2021-07-29 23:24:14 +0000
Commit:     Eric Joyner <erj@FreeBSD.org>
CommitDate: 2022-03-08 00:10:27 +0000

    iflib: Allow drivers to determine which queue to TX on
    
    Adds a new function pointer to struct if_txrx in order to allow
    drivers to set their own function that will determine which queue
    a packet should be sent on.
    
    Since this includes a kernel ABI change, bump the __FreeBSD_version
    as well.
    
    (This motivation behind this is to allow the driver to examine the
    UP in the VLAN tag and determine which queue to TX on based on
    that, in support of HW TX traffic shaping.)
    
    Signed-off-by: Eric Joyner <erj@FreeBSD.org>
    
    Reviewed by:    kbowling@, stallamr@netapp.com
    Tested by:      jeffrey.e.pieper@intel.com
    Sponsored by:   Intel Corporation
    Differential Revision:  https://reviews.freebsd.org/D31485
    
    (cherry picked from commit 213e91399b7998554d787bb290109ebe602aa279)
---
 sys/net/iflib.c | 12 ++++++++----
 sys/net/iflib.h | 11 +++++++++++
 sys/sys/param.h |  2 +-
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/sys/net/iflib.c b/sys/net/iflib.c
index 81cb66738454..aba3baaa1e50 100644
--- a/sys/net/iflib.c
+++ b/sys/net/iflib.c
@@ -209,6 +209,7 @@ struct iflib_ctx {
 #define isc_rxd_refill ifc_txrx.ift_rxd_refill
 #define isc_rxd_flush ifc_txrx.ift_rxd_flush
 #define isc_legacy_intr ifc_txrx.ift_legacy_intr
+#define isc_txq_select ifc_txrx.ift_txq_select
 	eventhandler_tag ifc_vlan_attach_event;
 	eventhandler_tag ifc_vlan_detach_event;
 	struct ether_addr ifc_mac;
@@ -4127,11 +4128,14 @@ iflib_if_transmit(if_t ifp, struct mbuf *m)
 	MPASS(m->m_nextpkt == NULL);
 	/* ALTQ-enabled interfaces always use queue 0. */
 	qidx = 0;
-	if ((NTXQSETS(ctx) > 1) && M_HASHTYPE_GET(m) && !ALTQ_IS_ENABLED(&ifp->if_snd))
+	/* Use driver-supplied queue selection method if it exists */
+	if (ctx->isc_txq_select)
+		qidx = ctx->isc_txq_select(ctx->ifc_softc, m);
+	/* If not, use iflib's standard method */
+	else if ((NTXQSETS(ctx) > 1) && M_HASHTYPE_GET(m) && !ALTQ_IS_ENABLED(&ifp->if_snd))
 		qidx = QIDX(ctx, m);
-	/*
-	 * XXX calculate buf_ring based on flowid (divvy up bits?)
-	 */
+
+	/* Set TX queue */
 	txq = &ctx->ifc_txqs[qidx];
 
 #ifdef DRIVER_BACKPRESSURE
diff --git a/sys/net/iflib.h b/sys/net/iflib.h
index fcf96215d398..42cab766a2fa 100644
--- a/sys/net/iflib.h
+++ b/sys/net/iflib.h
@@ -187,6 +187,7 @@ typedef struct if_txrx {
 	void (*ift_rxd_refill) (void * , if_rxd_update_t iru);
 	void (*ift_rxd_flush) (void *, uint16_t qsidx, uint8_t flidx, qidx_t pidx);
 	int (*ift_legacy_intr) (void *);
+	qidx_t (*ift_txq_select) (void *, struct mbuf *);
 } *if_txrx_t;
 
 typedef struct if_softc_ctx {
@@ -396,6 +397,16 @@ typedef enum {
  */
 #define IFLIB_PSEUDO_ETHER	0x80000
 
+/* The following IFLIB_FEATURE_* defines are for driver modules to determine
+ * what features this version of iflib supports. They shall be defined to the
+ * first __FreeBSD_version that introduced the feature.
+ */
+/*
+ * Driver can set its own TX queue selection function
+ * as ift_txq_select in struct if_txrx
+ */
+#define IFLIB_FEATURE_QUEUE_SELECT	1300527
+
 /*
  * These enum values are used in iflib_needs_restart to indicate to iflib
  * functions whether or not the interface needs restarting when certain events
diff --git a/sys/sys/param.h b/sys/sys/param.h
index 86ad3d3a4cfc..1d2f1154e655 100644
--- a/sys/sys/param.h
+++ b/sys/sys/param.h
@@ -60,7 +60,7 @@
  *		in the range 5 to 9.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 1300526	/* Master, propagated to newvers */
+#define __FreeBSD_version 1300527	/* Master, propagated to newvers */
 
 /*
  * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,